Rsu apparatus, base station apparatus, control node, and methods therein

ABSTRACT

A Road Side Unit (RSU) (120) transmits V2X report information to a control node (140) and transmits location-related information about the RSU (120) to the control node (140). The control node (140) determines, based on the received location-related information about the RSU (120), at least one of: one or more sending nodes; a transmission area; a distribution path; and a communication scheme, to distribute a V2X control message to a plurality of UEs. It is thus, for example, possible to contribute to achievement of a configuration in which, upon receiving V2X report information from an RSU, a server transmits a V2X control message based on the V2X report information to a plurality of vehicles or pedestrians.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation Application of U.S. application Ser.No. 15/755,611 filed Feb. 27, 2018, which is a National Stage ofInternational Application No. PCT/JP2016/002994, filed Jun. 21, 2016,claiming priority on Japanese Patent Application No. 2015-185291, filedSep. 18, 2015, the contents of all of which are incorporated herein byreference in their entirety.

TECHNICAL FIELD

The present disclosure relates to a radio communication system and, inparticular, to a V2X service.

BACKGROUND ART

Non-Patent Literature 1 discloses use cases and potential requirementsregarding Long Term Evolution (LTE) based Vehicle-to-Everything (V2X)services. The V2X means vehicular communications and includesVehicle-to-Vehicle (V2V) communications, Vehicle-to-Infrastructure (V2I)communications, and Vehicle-to-Pedestrian (V2P) communications. The V2Vcommunications or the V2V Services are communication or services betweenUser Equipments (UEs) that are installed in vehicles and use V2Vapplications. The V2I communications or the V2I Services arecommunications or services between a UE and a Road Side Unit (RSU), bothof which use V2I applications. The V2I communication includesInfrastructures-to-Vehicle (I2V) communications, unless otherwisespecified. Further, the term “UE” as used herein includes not only a UEinstalled in a vehicle but also a UE carried by a pedestrian. The RSU isan entity located on a road side and supports V2I Services includingtransmission and reception to and from vehicle UEs that use V2Iapplications. The RSU is installed in a base station, such as a LTE basestation (i.e., Evolved Node B (eNB)), or in a stationary UE. The V2Pcommunications or the V2P Services are communications or servicesbetween a vehicle UE and a pedestrian UE, both of which use the V2Iapplication. The V2P communications may be performed via an RSU and is,accordingly, referred to as V2I2P communications or P2I2Vcommunications.

Some use cases regarding the V2I Service disclosed in Non-PatentLiterature 1 will be introduced here. Non-Patent Literature 1 discloses,in Section 5.6 V2I Emergency Stop Use Case, a configuration in which avehicle and an RSU are each equipped with a Prose-enabled UEs and thevehicle and the RSU perform Proximity-based services (Prose)communication. ProSe communication is device-to-device (D2D)communication and includes direct communication between two or moreProSe-enabled UEs that are in proximity to each other. In this use case,a vehicle A transmits a message indicating an event, such as anemergency stop, to a service RSU. The service RSU receives this messagefrom the vehicle A and then relays this message to its surroundingvehicles. All vehicles within the transmission range from the serviceRSU are able to receive this message.

In the use case disclosed in Section 5.14 “V2X Road safety service viainfrastructure” of Non-Patent Literature 1, an RSU C detects that anaccident has occurred in the area where the RSU C manages. The RSU Cindicates the occurrence of this accident to a remote server (e.g., aTraffic Safety Server (TSS) or an Intelligent Transport Systems (ITS)server) and starts transmission of this information in the area. Theserver informs other RSUs near the RSU C that there is an accident inthe area managed by the RSU. The other RSUs start transmission of V2Xmessages indicating that there is an accident in the area indicated bythe RSU C.

CITATION LIST Non-Patent Literature

-   [Non-Patent Literature 1] 3GPP S1-151330 “3GPP TR 22.885 V0.2.0    Study on LTE Support for V2X services (Release 14)”, April, 2015

SUMMARY OF INVENTION Technical Problem

Consider a use case in which a server transmits, in response toreception of V2X report information (e.g., accident notification) froman RSU, a V2X control message, which is based on the V2X reportinformation, to a plurality of vehicles or pedestrians via a pluralityof base stations (eNBs) or a plurality of RSUs (e.g., Section 5.14 ofNon-Patent Literature 1). To achieve this use case, in oneimplementation, the server (or the base station) needs to determine ageographical area in which this V2X control message is to bedistributed, or determine one or more sending nodes (i.e., an RSU or abase station) to transmit this V2X control message to a plurality ofvehicles or pedestrians.

In another implementation, there may be a plurality of distributionpaths available to transmit the V2X control message to a plurality ofvehicles or pedestrians. For example, there may be a first availabledistribution path for a base station to transmit the message directly toa plurality of vehicle UEs or pedestrian UEs and a second availabledistribution path for a base station to transmit the message to aplurality of vehicle UEs or pedestrian UEs via one or more RSUs. In thiscase, the server (or the base station) needs to determine a distributionpath to be used to transmit the V2X control message.

In still another implementation, there may be a plurality ofcommunication schemes available to transmit the V2X control message to aplurality of vehicles or pedestrians. For example, a Cell BroadcastService (CBS), a Multimedia Broadcast/Multicast Service (MBMS), andgroupcast in D2D communication (e.g., ProSe communication) can be used.In this case, the server (or the base station) needs to determine acommunication scheme to be used to transmit the V2X control message.

One of the objects to be attained by embodiments disclosed herein is toprovide an apparatus, a method, and a program that contribute toachievement of a configuration in which, upon receiving V2X reportinformation from an RSU, a server transmits a V2X control message basedon this V2X report information to a plurality of vehicles orpedestrians. It should be noted that this object is merely one of theobjects to be attained by the embodiments disclosed herein. Otherobjects or problems and novel features will be made apparent from thedescriptions in the specification and the accompanying drawings.

Solution to Problem

In a first aspect, an RSU apparatus includes a wireless transceiver andat least one processor. The wireless transceiver is configured tocommunicate with a radio terminal installed in a vehicle. The at leastone processor is configured to transmit V2X report information to acontrol node and transmit location-related information about the RSUapparatus to the control node.

In a second aspect, a method in an RSU apparatus includes transmittingV2X report information to a control node and transmittinglocation-related information about the RSU apparatus to the controlnode.

In a third aspect, a base station apparatus includes a wirelesstransceiver and at least one processor. The wireless transceiver isconfigured to communicate with a plurality of radio terminals includingone or more Road Side Units (RSUs) supporting a Vehicle-to-Everything(V2X) service. The at least one processor is configured to transmit V2Xreport information received from a first RSU included in the one or moreRSUs to a control node and to transmit location-related informationabout the first RSU to the control node.

In a fourth aspect, a method in a base station apparatus includes: (a)communicating with a plurality of radio terminals including one or moreRoad Side Units (RSUs) supporting a Vehicle-to-Everything (V2X) service;and (b) transmitting V2X report information received from a first RSUincluded in the one or more RSUs to a control node and transmittinglocation-related information about the first RSU to the control node.

In a fifth aspect, a control node includes a memory and at least oneprocessor coupled to the memory. The at least one processor isconfigured to determine, based on location-related information about afirst Road Side Unit (RSU) supporting a Vehicle-to-Everything (V2X)service, at least one of: (a) one or more sending nodes to transmit aV2X control message generated based on V2X report informationtransmitted by the first RSU in such a way that a plurality of vehiclesare able to receive the V2X control message; (b) a geographical area inwhich the V2X control message is to be transmitted; (c) a logical areain which the V2X control message is to be transmitted; (d) adistribution path of the V2X control message to the one or more sendingnodes; and (e) a communication scheme to be used for transmission of theV2X control message.

In a sixth aspect, a method in a control node includes determining,based on location-related information about a first Road Side Unit (RSU)supporting a Vehicle-to-Everything (V2X) service, at least one of: (a)one or more sending nodes is to transmit a V2X control message generatedbased on V2X report information transmitted by the first RSU in such away that a plurality of vehicles are able to receive the V2X controlmessage; (b) a geographical area in which the V2X control message is tobe transmitted; (c) a logical area in which the V2X control message isto be transmitted; (d) a distribution path of the V2X control message tothe one or more sending nodes; and (e) a communication scheme to be usedfor transmission of the V2X control message.

In a seventh aspect, a program includes instructions (software codes)that, when loaded into a computer, cause the computer to perform themethod according to the above-described second, fourth, or sixth aspect.

Advantageous Effects of Invention

According to the above aspects, it is possible to provide an apparatus,a method, and a program that contribute to achievement of aconfiguration in which, upon receiving V2X report information from anRSU, a server transmits a V2X control message based on this V2X reportinformation to a plurality of vehicles or pedestrians.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram showing a configuration example of a radiocommunication system according to an embodiment;

FIG. 2 is a diagram showing a configuration example of a radiocommunication system according to an embodiment;

FIG. 3 is a diagram showing a configuration example of a radiocommunication system according to an embodiment;

FIG. 4 is a sequence diagram showing one example of operations of an RSUand a server according to an embodiment;

FIG. 5 is a flowchart showing one example of an operation of an RSUaccording to an embodiment;

FIG. 6 is a flowchart showing one example of an operation of a serveraccording to an embodiment;

FIG. 7 is a sequence diagram showing one example of operations of anRSU, a base station, and a server according to an embodiment;

FIG. 8 is a flowchart showing one example of an operation of a basestation according to an embodiment;

FIG. 9 is a sequence diagram showing one example of operations of anRSU, a base station, and a server according to an embodiment;

FIG. 10 is a sequence diagram showing one example of operations of anRSU, a base station, and a server according to an embodiment;

FIG. 11 is a block diagram showing a configuration example of an RSU anda base station according to an embodiment;

FIG. 12 is a block diagram showing a configuration example of an RSU anda radio terminal according to an embodiment; and

FIG. 13 is a block diagram showing a configuration example of a serveraccording to an embodiment.

DESCRIPTION OF EMBODIMENTS

Specific embodiments are described hereinafter in detail with referenceto the drawings. The same or corresponding elements are denoted by thesame reference signs throughout the drawings, and repetitivedescriptions will be omitted as necessary for clarity of explanation.

The following descriptions on the embodiments mainly focus on an EvolvedPacket System (EPS) that contains LTE and System Architecture Evolution(SAE). However, these embodiments are not limited to being applied tothe EPS and may be applied to other mobile communication networks orsystems such as 3GPP UMTS, 3GPP2 CDMA2000 systems (1×RTT, High RatePacket Data (HRPD)), global system for mobile communications (GSM(trademark))/General packet radio service (GPRS) systems, and WiMAXsystems.

FIG. 1 shows a configuration example of a radio communication systemaccording to some embodiments. Radio terminals (i.e., UEs) 100-102 areinstalled in vehicles. Each of the vehicle UEs 100-102 may beimplemented in an in-vehicle processing unit (e.g., a car navigationsystem). The vehicle UEs 100-102 each execute a V2I application tosupport the V2I Service. The UEs 100-102 may support another V2Xservice, i.e., a V2V Service or a V2P Service or both.

RSUs 120 and 121 are each installed on a road side. In the example shownin FIG. 1, the RSU 120 is installed near an intersection 110. The RSUs120 and 121 each may be equipped with, for example, but not limited to,a Prose-enabled UE, and may perform ProSe communication with the vehicleUEs 100-102 to provide the V2I Service. The RSUs 120 and 121 may eachserve as a ProSe UE-to-Network Relay (i.e., Relay UE). The ProSeUE-to-Network Relay mainly relays traffic (i.e., downlink and uplink)between a UE in out-of-coverage (i.e., remote UE) and the network. TheRSUs 120 and 121 each communicate with a base station (eNB) 130 in acellular communication network via a radio connection and alsocommunicate with a server 140 (e.g., an ITS server or a TSS) via the eNB130.

As already described above, Proximity-based services (ProSe) defined in3GPP Release 12 are one example of D2D communication. The D2Dcommunication includes at least one of Direct Communication and DirectDiscovery. In 3GPP Release 12, an inter-UE radio link used for DirectCommunication or Direct Discovery is referred to as a PC5 interface orSidelink. Accordingly, it can be said that ProSe is a general term forcommunications (or services) that use at least the Sidelink. In theexample shown in FIG. 1, the communication between the RSU 120 servingas a UE or a Relay UE and the UE 100 or 101 may use the Sidelink, andthe communication between two or more UEs may also use the Sidelink. In3GPP Release 12, sidelink transmission uses the same frame structure asuplink and downlink transmission of the Long Term Evolution (LTE), anduses a subset of uplink resources in frequency and time domains. In 3GPPRelease 12, a UE performs sidelink transmission by using Single-CarrierFrequency-Division Multiple Access (SC-FDMA), which is similar to thescheme used in uplink transmission.

Upon receiving a notification 150 from the vehicle UE 100, the RSU (UE)120 generates V2X report information 160 based on the notification 150,and sends the generated V2X report information 160 to the server 140 viathe eNB 130. For example, the RSU (UE) 120 may inspect (or detect) thecontent of the notification 150 and generate the V2X report information160 that contains the content of the notification 150. Alternatively,without inspecting the notification 150 from the UE 100, the RSU (UE)120 may generate and transmit the V2X report information 160 thatcontains the notification 150 from the UE 100.

The notification 150 may be, for example, but not limited to, a messageregarding an emergency stop or an accident regarding a vehicle equippedwith the UE 100, a message regarding a driving status of the vehicle, ora message regarding conditions of nearby roads (e.g., a traffic jam,weather, an accident, an obstacle on the road). The UE 100 mayincorporate into the notification 150 a V2V message received fromanother vehicle (UE) via V2V communication, or a message derived fromthe V2V message. Further, the RSU (UE) 120 may receive a V2V messagetransmitted by the UE 100 via V2V communication as the notification 150.In this case, the RSU (UE) 120 may use this V2V message or a messagederived from this V2V message as the V2X report information 160. Notethat the RSU (UE) 120 may autonomously generate the V2X reportinformation 160 without depending on the reception of the notification150 from the vehicle UE 100. For example, the RSU (UE) 120 may monitorconditions of roads in its management area (e.g., a traffic jam,weather, an accident, or an obstacle on the road) using sensors, such ascameras and weather instruments, and generate the V2X report information160 based on the result of the monitoring.

Upon receiving the V2X report information 160 from the RSU (UE) 120, theserver 140 generates a V2X control message 170 based on the V2X reportinformation 160. The V2X control message 170 may include, for example, awarning about road conditions (e.g., occurrence of an accident or atraffic jam) or detour route guidance. The server 140 transmits the V2Xcontrol message 170 in such a way that vehicle UEs including the vehicleUEs 100-102 can receive the V2X control message 170. In the exampleshown in FIG. 1, the V2X control message 170 is transmitted from theserver 140 to the RSUs (UEs) 120 and 121 via the eNB 130 and thentransmitted to the vehicle UEs 100-102 by each RSU (UE).

Note that the distribution path of the V2X control message 170 from theserver 140 to the UEs 100-102 shown in FIG. 1 is merely an example. Inother words, the server 140 can use a plurality of distribution paths todistribute the V2X control message 170 to the UEs 100-102. Further,these distribution paths can use communication schemes different fromeach other. Accordingly, the server 140 can use a plurality ofdistribution paths and a plurality of communication schemes todistribute the V2X control message 170 to the UEs 100-102. Thecommunication schemes include, for example, a Cell Broadcast Service(CBS), a Multimedia Broadcast/Multicast Service (MBMS), and groupcast inD2D communication (e.g., ProSe communication). In the groupcast, forexample, a receiver side (e.g., UE) determines whether informationshould be received by performing certain filtering processing, andrestores this information if this information should be received. In thecertain filtering processing, for example, a UE may restore a groupidentifier contained in the layer-2 header and determine whether thisgroup identifier should be received. The group identifier may beconfigured in the receiver side (e.g., UE) in advance or may be sentfrom the transmitter side (e.g., eNB or application server). The groupidentifier may be information indicating a specific group (e.g., UEs) ormay be a V2X SA Index (ID).

FIG. 2 shows another distribution path of the V2X control message 170different from the distribution path shown in FIG. 1. In the exampleshown in FIG. 2, the V2X control message 170 is transmitted from the eNB130 directly to the vehicle UEs 100-102 without traversing the RSUs(UEs) 120 and 121. For example, the eNB 130 may broadcast/multicast theV2X control message 170 in such a way that a plurality of UEs locatedwithin a cell served by the eNB 130 are able to receive this message.

In some implementations, the eNB 130 may transmit the V2X controlmessage 170 on the user plane (U-plane). Specifically, the eNB 130 maytransmit the V2X control message 170 using a broadcast bearer, amulticast bearer, or a Point-to-Multipoint (PTM) bearer. The V2X controlmessage 170 may be transmitted on a Data Radio Bearer for carrying MBMSdata, i.e., an MBMS Radio Bearer (MRB) or a Point-to-Multipoint (PTM)Radio Bearer. In MBMS, the same data (message) is transmitted to aplurality of UEs via a common MRB (or a PTM radio bearer).

Alternatively, in some implementations, the eNB 130 may transmit the V2Xcontrol message 170 on the control plane (C-plane). The eNB 130 maytransmit the V2X control message 170 on a Broadcast Control Channel(BCCH) that carries a System Information Block (SIB). For example, AaPublic Warning System (PWS) for CBS in LTE/Evolved Packet System (EPS)may be used. The 3GPP specifies, as the PWS, Earthquake and TsunamiWarning System (ETWS) used in Japan, Commercial Mobile Alert System(CMAS) used in North America, Korean Public Alert System (KPAS) used inKorea, and EU-ALERT used in European countries. In the PWS, warningmessages (Primary Notification and Secondary Notification) aretransmitted by SIB 10 and SIB 11. When the V2X control message 170 istransmitted on the C-plane, it may be transmitted from the server 140 tothe eNB 130 via a Mobility Management Entity (MME). In this case, theV2X control message may be transmitted by a WRITE-REPLACE WARNINGREQUEST message.

FIG. 3 shows another configuration example of the radio communicationsystem according to some embodiments. In the example shown in FIG. 3,each of RSUs 320 and 321 serves as a base station (eNB). In response toreceiving a notification 150 from the vehicle UE 100, the RSU (eNB) 320generates the V2X report information 160 based on the notification 150and sends the generated V2X report information 160 to the server 140. Inresponse to receiving the V2X report information 160 from the RSU (eNB)320, the server 140 generates a V2X control message 170 based on the V2Xreport information 160. Similar to the examples shown in FIGS. 1 and 2,the server 140 transmits the V2X control message 170 in such a way thata plurality of vehicle UEs including the vehicle UEs 100-102 can receivethe V2X control message 170. However, in the example shown in FIG. 3,the V2X control message 170 is transmitted from the server 140 to theRSUs (eNBs) 320 and 321 and then transmitted to the vehicle UEs 100-102by the RSUs (eNBs). The RSUs (eNBs) 320 and 321 may transmit the V2Xcontrol message 170 either on the U-plane or on the C-plane, similar tothe eNB 130 shown in FIG. 2.

FIGS. 1-3 show the examples in which the V2X control message 170 isreceived by the plurality of vehicle UEs 100-102. However, the V2Xcontrol message 170 may be received by pedestrians (i.e., pedestrianUEs).

In the configurations shown in FIGS. 1 and 2, the communication betweenthe eNB 130 and the RSU 120 serving as a UE may use a dedicated carrierfrequency band f1 reserved for the V2X service. Alternatively, thecommunication between the RSU (UE) 120 and the eNB 130 may use a sharedfrequency band (or a Shared spectrum) f2 that is not licensed to anyoperator or is shared by a plurality of operators. Such a communicationusing a shared frequency is referred to as Licensed Shared Access (LSA).Alternatively, the communication between the RSU (UE) 120 and the eNB130 may use a carrier frequency band f3 that is licensed to an operatorof the cellular communication network. In a similar way, communicationbetween the UE 100 and the RSU (UE) 120 and communication between the UE100 and the eNB 130 may use any one of the above-described frequencybands f1, f2, and f3. Further, in the configuration shown in FIG. 3,communication between the UE 100 and the RSU 320 serving as an eNB mayalso use any one of the above-described frequency bands f1, f2, and f3.Furthermore, in the configuration shown in FIGS. 1-3, communicationbetween UEs (not shown) may also use any one of the above-describedfrequency bands f1, f2, and f3.

The UEs 100-102 and the RSUs (UEs) 120-121 serving as UEs may receiveV2X configuration from the network (e.g., the eNB 130, the RSU 320, or aV2X controller (not shown)). The V2X configuration may indicatemeasurement configuration for a carrier frequency band that is used forthe V2X service. Additionally or alternatively, the V2X configurationmay include a radio resource configuration for the V2X service.Additionally or alternatively, the V2X configuration may indicate aradio resource pool to be used for autonomous resource selectionperformed by the UEs 100-102 or the RSUs 120-121 for the V2X service.The V2X configuration may indicate allocation of dedicated radioresources to the UEs 100-102 or the RSUs 120-121 for the V2X service.

A V2X service Area (SA) may be defined to specify an area where the sameV2X configuration is applied. The V2X SA may be defined in any one of: adedicated carrier frequency band f1 reserved for the V2X service; ashared frequency band f2 for LSA; and a carrier frequency band f3licensed to an operator of the cellular communication network. Forexample, a cell may be defined on the frequency band f3, and meanwhilethe V2X SA may be defined on the frequency band f1 or f2. The V2X SA maybe defined independently from a cell(s) or may be defined in associationwith a cell(s). In the former case, there may be a plurality of V2X SAsin one cell or there may be a V2X SA across a plurality of cells (i.e.,a V2X SA that at least partially covers each of the plurality of cells).In the latter case, one V2X SA may be defined by one cell or by acombination of cells. Further, when a UE moves between cells belongingto the same V2X SA (i.e., the UE executes performs a cell re-selectionor handover between the cells), the UE may continue the V2X servicewithout suspending this service. Alternatively, the UE may suspend theV2X service while performing the cell re-selection or handover and thenresume this service after completion of the cell re-selection orhandover. That is, it can be considered that the V2X SA is a “validarea” of the V2X configuration. Information about the V2X SA (e.g., V2XSA Index (ID)) may be transmitted as one of information elements (IEs)contained in the V2X configuration or may be transmitted by a message orsignalling other than the V2X configuration. For example, the eNB 130 orthe RSU (eNB) 320 may incorporate the information about the V2X SA intothe V2X configuration and then transmit the V2X configuration in thefrequency band f3. In this case, the RSUs (UEs) 120 and 121 may furthertransmit information about the V2X SA on the frequency band f1 or f2.The RSUs (UEs) 120 and 121 may broadcast or groupcast the informationabout the V2X SA or transfer (or relay) this information to the UEs100-102.

In the configurations shown in FIGS. 1-3, the server 140 may beco-located in the same site together with the eNB 130 or the RSU 320 or321 serving as an eNB. Such a server is referred to as a Mobile EdgeComputing (MEC) server. Alternatively, the server 140 may be installedat a remote site that is geographically located apart from the sitewhere the eNB 130 (or the RSU 320 or 321) is installed and communicatewith the eNB 130 via one or more entities (e.g., a Mobility ManagementEntity, a Packet Data Network Gateway (P-GW), and a Serving Gateway(S-GW)) in the cellular communication network.

The server 140 is preferably able to determine one or more sending nodesto transmit the V2X control message 170, which is generated based on theV2X report information 160 from the RSU 120 (or 320). The one or moresending nodes includes one or more eNBs, one or more RSUs each serving aUE, RSUs each serving as an eNB, or any combination thereof. The server140 may designate a geographical area or a logical area, instead ofspecifically designating the one or more sending nodes. Alternatively,the server 140 may designate a logical area as well as designating theone or more sending nodes or the geographical area. The geographicalarea may be indicated by, for example, location information (e.g., GNSSlocation information), a cell, a tracking area (TA), a V2X service area(V2X SA), or information about the physical management area managed byone or more sending nodes (e.g., RSU, eNB), or any combination thereof.The logical area may be indicated by, for example, a network identifier(e.g., PLMN), an identifier assigned to a sending node, or a groupidentifier (e.g., RSU Group ID, eNB Group ID) configured for each groupformed of one or more sending nodes, or any combination thereof.

Furthermore, there may be a plurality of distribution paths and aplurality of communication schemes available to the server 140 totransmit the V2X control message 170 to the plurality of UEs 100-102, asdescribed with reference to FIGS. 1-3. In this case, the server 140 ispreferably able to determine (select) a distribution path or acommunication scheme or both to transmit the V2X control message 170.

The following description provides some embodiments for enabling theserver 140 to easily and efficiently determine at least one of: (a) oneor more sending nodes to transmit the V2X control message 170; (b) ageographical area in which the V2X control message 170 is to betransmitted; (c) a logical area in which the V2X control message is tobe transmitted; (d) a distribution path of the V2X control message toone or more sending nodes; and (e) a communication scheme to be used fortransmission of the V2X control message 170.

First Embodiment

In some implementations, the RSU 120 serving as a UE or the RSU 320serving as an eNB may transmit its location-related information to theserver 140. This location-related information allows the location of thetransmission source RSU of the V2X report information 160 to be checked.The location of the RSU checked by using the location-relatedinformation may be a geographical location (e.g., the locationcoordinates or the location address) or may be a relationship with otherRSUs or other eNBs (e.g., an adjacency relationship or a master-slaverelationship). Specifically, this location-related information includesat least one of: a pre-configured RSU identifier; a pre-configuredmanagement area identifier; and location information indicating locationcoordinates or a location address.

The RSU identifier may be an ID (RSU ID) individually assigned to eachRSU or may be an ID (RSU Group ID) assigned to an RSU group including aplurality of RSUs. The RSU identifier may be an IP address configured inthe RSU. The RSU identifier may be a cell ID of a cell served by theRSU. The management area identifier may indicate a management area towhich the RSU belongs, and may be a cell ID of a cell served by the eNB130. The RSU identifier or the management area identifier may be an IDof a network operator (e.g., Public Land Mobile Network (PLMN) ID). Thelocation information indicating location coordinates or a locationaddress may be Global Navigation Satellite System (GNSS) locationinformation obtained by a GNSS receiver installed in the RSU.

The RSU 120 or 320 may transmit its location-related informationtogether with the V2X report information 160. Alternatively, the RSU 120or 320 may transmit its location-related information using a messageother than the V2X report information 160.

The server 140 may determine, using the location-related informationabout the transmission source RSU of the V2X report information 160, atleast one of: (a) one or more sending nodes; (b) a geographical area;(c) a logical area; (d) a distribution path; and (e) a communicationscheme, to distribute the V2X control message 170. The communicationscheme may be any one of (1) MBMS (e.g., Multicast-broadcastsingle-frequency network (MBSFN), Single Cell Point To Multipoint(SC-PTM)), (2) CBS, and (3) groupcast or broadcast in D2D communication(e.g., ProSe communication). Alternatively, the communication scheme maybe selected from among a plurality of communication schemes including atleast two of them.

When the MBMS is used to distribute the V2X control message 170, theserver 140 may serve as a Broadcast Multicast Service Center (BM-SC).Alternatively, the server 140 may communicate with the BM-SC via anApplication Programming Interface (API) and may ask the BM-SC todistribute the V2X control message 170.

When the CBS is used to distribute the V2X control message 170, theserver 140 may serve as one or both of a Cell Broadcast Entity (CBE) anda Cell Broadcast Center (CBC).

The server 140 may determine one or more sending RSUs as the one or moresending nodes based on the location-related information about thetransmission source RSU of the V2X report information 160, and furtherdetermine at least one of a distribution path and a communication schemeto distribute the V2X control message 170 based on a type(s) of thedetermined one or more sending RSUs. The type of a sending RSU may be,for example, a UE type (i.e., an RSU serving as a UE) or an eNB type(i.e., an RSU serving as an eNB).

FIG. 4 is a sequence diagram showing a process 400, which is an exampleof operations of the RSUs 120 and 320 and the server 140. In Step 401,the reporting RSU 120 or 320 serving as a UE or an eNB transmits, to theserver 140, its location-related information (i.e., location-relatedinformation about the RSU) together with V2X report information 160.

In Step 402, the server 140 generates a V2X control message 170 based onthe V2X report information 160. The server 140 may further take intoaccount the location-related information about the reporting RSU togenerate the V2X control message 170.

In Step 403, the server 140 determines, based on the location-relatedinformation about the reporting RSU, at least one of: (a) one or moresending nodes to transmit the V2X control message 170, (b) ageographical area in which the V2X control message 170 to betransmitted, (c) a logical area in which the V2X control message 170 tobe transmitted, (d) a distribution path of the V2X control message toone or more sending nodes, and (e) a communication scheme to be used fortransmission of the V2X control message 170 (i.e., Determine node(s),area, route(s), or scheme(s) for message delivery). The server 140 mayfurther take into account the type or content of the V2X reportinformation 160 to determine them.

FIG. 5 is a flowchart showing a process 500, which is an example ofoperations of the RSUs 120 and 320. In Step 501, the reporting RSU 120or 320 serving as an UE or an eNB receives a notification 150 from avehicle or pedestrian UE 100 via V2I communication. In Block 502, inresponse to receiving the notification 150, the reporting RSU 120 or 320transmits V2X report information 160 and its location-relatedinformation to the server 140.

According to the operations (or method) shown in FIG. 5, the reportingRSU 120 or 320 can provide its location-related information to theserver 140, thereby contributing to facilitating the determination bythe server 140 of at least one of: the sending node(s); the area; thedistribution path; and the communication scheme, to distribute the V2Xcontrol message 170.

FIG. 6 is a flowchart showing a process 600, which is an example of anoperation of the server 140. In Step 601, the server 140 receives fromthe reporting RSU 120 or 320 V2X report information 160 andlocation-related information about the reporting RSU. In Step 602, usingthe received location-related information about the reporting RSU, theserver 140 determines at least one of: sending node(s), an area; adistribution path; and a communication scheme, to distribute the V2Xcontrol message 170.

According to the operation (or method) shown in FIG. 6, the server 140uses the location-related information about the reporting RSU 120 or 320and thus can easily and efficiently determine at least one of: thesending node(s); the area; the distribution path; and the communicationscheme, to distribute the V2X control message 170.

Second Embodiment

In the configuration shown in FIG. 1 or 2, the location-relatedinformation about the reporting RSU 120 may be generated by the eNB 130,not by the reporting RSU 120. That is, in response to receiving V2Xreport information 160 from the reporting RSU 120, the eNB 130 maytransmit this V2X report information 160 to the server 140 and furthertransmit, to the server 140, location-related information that allowsthe location of the reporting RSU 120 to be checked. The eNB 130 maystore location-related information about nearby RSUs (or RSUs connectedto the eNB 130) in advance. The eNB 130 may receive location-relatedinformation about nearby RSUs from these RSUs and then store thisinformation. Alternatively, location-related information about nearbyRSUs may be pre-configured in the eNB 130 by an operator. Alternatively,the eNB 130 may transmit, to the server 140, location-relatedinformation that allows the location of the eNB 130 to be checked, inplace of the location-related information about the reporting RSU 120.The location-related information that allows the location of the eNB 130to be checked may include at least one of: location informationindicating a geographical location (e.g., location coordinates or alocation address) of the eNB 130; an identifier of the eNB 130; and anidentifier of a cell served by the eNB 130 in which the reporting RSU120 is located.

FIG. 7 is a sequence diagram showing a process 700, which is an exampleof operations of the UE 100, the UE 102, the RSU 120, the RSU 121, theeNB 130, and the server 140. In Step 701, the vehicle UE 100 transmits anotification 150 to the RSU 120 serving as a UE. In Step 702, thereporting RSU 120 transmits V2X report information 160 to the server 140or the eNB 130. In Step 702, the reporting RSU 120 may transmit the V2Xreport information 160 either on the control plane (C-plane) or the userplane (U-plane). When the reporting RSU 120 transmits the information onthe C-plane, it may use an existing SRB (e.g., SRB2) in LTE or may useSRBx (e.g., SRB3) that is newly defined for the V2X service.

In Step 703, in response to receiving the V2X report information 160from the reporting RSU 120, the eNB 130 transmits to the server 140 aV2X report message containing the V2X report information 160 and thelocation-related information about the reporting RSU 120. In Step 703,the eNB 130 may transmit the V2X report message either on the controlplane (C-plane) or on the user plane (U-plane).

The processes of the server 140 in Steps 704 and 705 are similar tothose in Steps 402 and 403 shown in FIG. 4. In the example shown in FIG.7, the sending node(s) determined in Step 705 includes the eNB 130 orthe RSU 121 or both. The one or more sending nodes determined in Step705 may include the reporting RSU 120.

In Step 706, the server 140 transmits a V2X control message 170 to theeNB 130 in accordance with the determination in Step 705. In Step 707,the eNB 130 transfers the V2X control message 170 to the sending RSU 121in response to receiving the V2X control message 170. In Step 708, thesending RSU 121 transfers the V2X control message 170 to the vehicle UE102. When the one or more sending nodes determined in Step 705 includesthe reporting RSU 120, the eNB 130 transfers the V2X control message 170to the RSU 120 in Step 709. In Step 710, the reporting RSU 120 serves asa sending RSU and transfers the V2X control message 170 to the vehicleUE 100 and the vehicle UE 101 (not shown).

FIG. 8 is a flowchart showing a process 800, which is an example of anoperation of the eNB 130. In Step 801, the eNB 130 receives V2X reportinformation 160 from the reporting RSU 120. In Step 802, the eNB 130transmits the V2X report information 160 and the location-relatedinformation about the reporting RSU 120 to the server 140.

According to the operation (or method) shown in FIG. 8, the eNB 130provides the server 140 with the location-related information about thereporting RSU 120, thereby contributing to facilitating thedetermination by the server 140 of at least one of: the sending node(s);the area; the distribution path; and the communication scheme, todistribute the V2X control message 170.

Third Embodiment

In some implementations, in place of the server 140, the eNB 130 or theRSU 320 serving as an eNB may determine at least one of: a sendingnode(s); an area; a distribution path; and a communication scheme, todistribute a V2X control message 170. Specifically, the server 140 maydetermine at least one of the sending node(s), the area, and thedistribution path, and then the eNB 130 (or the RSU 320) may determineat least the communication scheme. Alternatively, the server 140 maydetermine at least the communication scheme and then the eNB 130 (or theRSU 320) may determine at least one of the sending node(s), the area,and the distribution path.

FIG. 9 is a sequence diagram showing a process 900, which is an exampleof operations of the UE 100, the UE 102, the RSUs 120 and 320, the RSU121, the eNB 130, and the server 140. In Step 901, the vehicle UE 100transmits a notification 150 to the RSU 120 or 320 serving as a UE or aneNB. In Step 902, the reporting RSU 120 or 320 transmits itslocation-related information (i.e., location-related information of RSU)to the server 140 together with V2X report information 160. In Step 902,the reporting RSU 120 or 320 may transmit the V2X report information 160on the user plane (U-plane).

In Step 903, the server 140 generates a V2X control message 170 based onthe V2X report information 160. The server 140 may further take intoaccount the location-related information about the reporting RSU togenerate the V2X control message 170.

In Step 904, the server 140 transmits the V2X control message 170 to theeNB 130 and also transmits the location-related information about thereporting RSU 120 or 320 to the eNB 130.

In Step 905, the eNB 130 determines at least one of: (a) one or moresending nodes to transmit the V2X control message 170 (i.e., one or moreRSUs); (b) a geographical area in which the V2X control message 170 isto be transmitted; (c) a logical area in which the V2X control message170 is to be transmitted; (d) a distribution path of the V2X controlmessage to one or more sending nodes; and (e) a communication scheme tobe used for transmission of the V2X control message 170 (i.e., Determinenode(s), area, route(s), or scheme(s) for message delivery). In theexample shown in FIG. 9, the sending node(s) determined in Step 905includes the RSU 121. The one or more sending nodes determined in Step905 may include the reporting RSU 120 or 320.

In Step 906, the eNB 130 transfers the V2X control message 170 to thesending RSU 121 in accordance with the determination in Step 905. InStep 907, the sending RSU 121 transfers the V2X control message 170 tothe vehicle UE 102. When one or more sending nodes determined in Step905 includes the reporting RSU 120 or 320, the eNB 130 transfers the V2Xcontrol message 170 to the RSU 120 or 320 in Step 908. In Step 909, thereporting RSU 120 or 320 serves as a sending RSU and transfers the V2Xcontrol message 170 to the vehicle UE 100 and the vehicle UE 101 (notshown).

According to the operations (or method) shown in FIG. 9, the basestation 130 uses the location-related information about the reportingRSU 120 or 320 and thus can easily and efficiently determine at leastone of the sending node(s), the area, the distribution path, and thecommunication scheme, to distribute the V2X control message 170.

FIG. 10 is a sequence diagram showing a process 1000, which is anotherexample of operations of the UE 100, the UE 102, the RSUs 120 and 320,the RSU 121, the eNB 130, and the server 140. Processes in Steps 1001,1002, and 1003 are similar to those in Steps 701, 702, and 703 shown inFIG. 7. However, the V2X report message transmitted in Step 1003 doesnot need to include the location-related information about the reportingRSU 120.

In Step 1004, in response to receiving the V2X report message containingthe V2X report information 160, the server 140 generates the V2X controlmessage 170. The server 140 takes into account the V2X reportinformation 160 to generate the V2X control message 170. The server 140may further take into account the location-related information about thereporting RSU to generate the V2X control message 170.

In Step 1005, the server 140 transmits the V2X control message 170 tothe eNB 130.

In Step 1006, the eNB 130 determines at least one of: (a) one or moresending nodes to transmit the V2X control message 170 (i.e., one or moreRSUs); (b) a geographical area in which the V2X control message 170 isto be transmitted; (c) a logical area in which the V2X control message170 is to be transmitted; (d) a distribution path of the V2X controlmessage to one or more sending nodes; and (e) a communication scheme tobe used for transmission of the V2X control message 170 (i.e., Determinenode(s), area, route(s), or scheme(s) for message delivery). In theexample shown in FIG. 10, the sending node(s) determined in Step 1006includes the RSU 121. The one or more sending nodes determined in Step1006 may include the reporting RSU 120.

To achieve the determination of the sending node(s) by the eNB 130 inStep 1006, the eNB 130 may store location-related information aboutnearby RSUs (or RSUs connected to the eNB 130) in advance. The eNB 130may receive location-related information about nearby RSUs from theseRSUs and then store this information. Alternatively, location-relatedinformation about nearby RSUs may be pre-configured in the eNB 130 by anoperator.

In Step 1007, the eNB 130 transfers the V2X control message 170 to thesending RSU 121 in accordance with the determination in Step 1006. InStep 1008, the sending RSU 121 transfers the V2X control message 170 tothe vehicle UE 102. When the one or more sending nodes determined inStep 1006 includes the reporting RSU 120, the eNB 130 transfers the V2Xcontrol message 170 to the RSU 120 in Step 1009. In Step 1010, thereporting RSU 120 serves as a sending RSU and transfers the V2X controlmessage 170 to the vehicle UE 100 and the vehicle UE 101 (not shown).

In this embodiment, the eNB 130 may further take into account a type orcontent of the V2X report information 160 to determine at least one of:one or more sending nodes; an area; a distribution path; and acommunication scheme, to distribute the V2X control message 170. In someimplementations, to recognize the type or content of the V2X reportinformation 160, the eNB 130 may execute deep packet inspection on thepacket(s) that carries the V2X report information 160 and detect thetype or content of the V2X report information.

Alternatively, the eNB 130 may detect the type or content of the V2Xreport information in accordance with a bearer that is used to transmitthe V2X control message 170 from the server 140 to the eNB 130. In thiscase, one or more bearers between the server 140 and the eNB 130 areassociated with respective types or contents of the V2X control message170. The server 140 transmits the V2X control message 170 using a bearer(or IP flow) associated with the type or content of the V2X controlmessage 170 to be transmitted.

Alternatively, the server 140 may send an indication regarding the typeor content of the V2X control message 170 to the eNB 130. This operationis efficient when the server 140 is a MEC server.

The following provides configuration examples of the UEs 100-102, theRSUs 120 and 320, the eNB 130, and the server 140 described in the aboveembodiments. FIG. 11 is a block diagram showing a configuration exampleof the eNB 130. The RSU 320, which serves as an eNB, may have aconfiguration similar to that shown in FIG. 11. Referring to FIG. 11,the eNB 130 includes an RF transceiver 1101, a network interface 1103, aprocessor 1104, and a memory 1105. The RF transceiver 1101 performsanalog RF signal processing to communicate with UEs. The RF transceiver1101 may include a plurality of transceivers. The RF transceiver 1101 iscoupled to an antenna 1102 and the processor 1104. The RF transceiver1101 receives modulated symbol data (or OFDM symbol data) from theprocessor 1104, generates a transmission RF signal, and supplies thetransmission RF signal to the antenna 1102. Further, the RF transceiver1101 generates a baseband reception signal based on a reception RFsignal received by the antenna 1102 and supplies the baseband receptionsignal to the processor 1104.

The network interface 1103 is used to communicate with the network node(e.g., other eNBs, Mobility Management Entity (MME), Serving Gateway(S-GW), and TSS or ITS server). The network interface 1103 may include,for example, a network interface card (NIC) conforming to the IEEE 802.3series.

The processor 1104 performs data plane processing including digitalbaseband signal processing and control plane processing for radiocommunication. In the case of LTE and LTE-Advanced, for example, thedigital baseband signal processing performed by the processor 1104 mayinclude signal processing of a PDCP layer, an RLC layer, a MAC layer,and a PHY layer. Further, the signal processing performed by theprocessor 1104 may include signal processing of a GTP-U·UDP/IP layer forX2-U and S1-U interfaces. Further, the control plane processingperformed by the processor 1104 may include processing of an X2APprotocol, an S1-MME protocol, and an RRC protocol.

The processor 1104 may include a plurality of processors. The processor1104 may include, for example, a modem processor (e.g., a DSP) thatperforms the digital baseband signal processing, a processor (e.g., aDSP) that performs signal processing of the GTP-U·UDP/IP layer for X2-Uand S1-U interfaces, and a protocol stack processor (e.g., a CPU or anMPU) that performs the control plane processing.

The memory 1105 is composed of a combination of a volatile memory and anon-volatile memory. The memory 1105 may include a plurality of memorydevices that are physically independent from each other. The volatilememory is, for example, a Static Random Access Memory (SRAM), a DynamicRAM (DRAM), or a combination thereof. The non-volatile memory is a maskRead Only Memory (MROM), an Electrically Erasable Programmable ROM(EEPROM), a flash memory, a hard disc drive, or any combination thereof.The memory 1105 may include a storage that is located away from theprocessor 1104. In this case, the processor 1104 may access the memory1105 via the network interface 1103 or an I/O interface (not shown).

The memory 1105 may store software modules (computer programs) includinginstructions and data to perform the processing by the eNB 130 describedin the above embodiments. In some implementations, the processor 1104may be configured to load the software modules from the memory 1105 andexecute the loaded software modules, thereby performing processing ofthe eNB 130 described in the above embodiments.

FIG. 12 is a block diagram showing a configuration example of the RSU120 serving as a UE (or a Relay UE). The UEs 101 and 102 may haveconfigurations similar to the configuration shown in FIG. 12. A RadioFrequency (RF) transceiver 1201 performs analog RF signal processing tocommunicate with the eNB 130. The analog RF signal processing performedby the RF transceiver 1201 includes frequency up-conversion, frequencydown-conversion, and amplification. The RF transceiver 1201 is coupledto an antenna 1202 and a baseband processor 1203. That is, the RFtransceiver 1201 receives modulated symbol data (or OFDM symbol data)from the baseband processor 1203, generates a transmission RF signal,and supplies the transmission RF signal to the antenna 1202. Further,the RF transceiver 1201 generates a baseband reception signal based on areception RF signal received by the antenna 1202, and supplies thebaseband reception signal to the baseband processor 1203.

The baseband processor 1203 performs digital baseband signal processing(i.e., data plane processing) and control plane processing for radiocommunication. The digital baseband signal processing includes (a) datacompression/decompression, (b) data segmentation/concatenation, (c)composition/decomposition of a transmission format (i.e., transmissionframe), (d) channel coding/decoding, (e) modulation (i.e., symbolmapping)/demodulation, and (f) generation of OFDM symbol data (i.e.,baseband OFDM signal) by Inverse Fast Fourier Transform (IFFT). On theother hand, the control plane processing includes communicationmanagement of layer 1 (e.g., transmission power control), layer 2 (e.g.,radio resource management and hybrid automatic repeat request (HARQ)processing), and layer 3 (e.g., signalling regarding attach, mobility,and call management).

In the case of LTE and LTE-Advanced, for example, the digital basebandsignal processing performed by the baseband processor 1203 may includesignal processing of a Packet Data Convergence Protocol (PDCP) layer, aRadio Link Control (RLC) layer, the MAC layer, and the PHY layer.Further, the control plane processing performed by the basebandprocessor 1203 may include processing of a Non-Access Stratum (NAS)protocol, an RRC protocol, and MAC CEs.

The baseband processor 1203 may include a modem processor (e.g., aDigital Signal Processor (DSP)) that performs the digital basebandsignal processing and a protocol stack processor (e.g., a CentralProcessing Unit (CPU) or a Micro Processing Unit (MPU)) that performsthe control plane processing. In this case, the protocol stackprocessor, which performs the control plane processing, may beintegrated with an application processor 1204 described in thefollowing.

The application processor 1204 is also referred to as a CPU, an MPU, amicroprocessor, or a processor core. The application processor 1204 mayinclude a plurality of processors (processor cores). The applicationprocessor 1204 executes a system software program (Operating System(OS)) and various application programs (e.g., a voice call application,a WEB browser, a mailer, a camera operation application, and a musicplayer application) loaded from a memory 1206 or from another memory(not shown), thereby providing various functions of the RSU 120.

In some implementations, as represented by a dashed line (1205) in FIG.12, the baseband processor 1203 and the application processor 1204 maybe integrated on a single chip. In other words, the baseband processor1203 and the application processor 1204 may be implemented in a singleSystem on Chip (SoC) device 1205. An SoC device may be referred to as asystem Large Scale Integration (LSI) or a chipset.

The memory 1206 is a volatile memory, a non-volatile memory, or acombination thereof. The memory 1206 may include a plurality of memorydevices that are physically independent from each other. The volatilememory is, for example, a Static Random Access Memory (SRAM), a DynamicRAM (DRAM), or a combination thereof. The non-volatile memory is, forexample, a Mask Read Only memory (MROM), an Electrically ErasableProgrammable ROM (EEPROM), a flash memory, a hard disc drive, or anycombination thereof. The memory 1206 may include, for example, anexternal memory device that can be accessed from the baseband processor1203, the application processor 1204, and the SoC 1205. The memory 1206may include an internal memory device that is integrated in the basebandprocessor 1203, the application processor 1204, or the SoC 1205.Further, the memory 1206 may include a memory in a Universal IntegratedCircuit Card (UICC).

The memory 1206 may store software modules (computer programs) includinginstructions and data to perform processing by the RSU 120 described inthe above embodiments. In some implementations, the baseband processor1203 or the application processor 1204 may load the software modulesfrom the memory 1206 and execute the loaded software modules, therebyperforming the processing of the RSU 120 described in the aboveembodiments.

FIG. 13 is a block diagram showing a configuration example of the server140. Referring to FIG. 13, the server 140 includes a network interface1301, a processor 1302, and a memory 1303. The network interface 1301 isused to communicate with the network node (e.g., the eNodeB 130, theMME, or the P-GW). The network interface 1301 may include, for example,a network interface card (NIC) conforming to the IEEE 802.3 series.

The processor 1302 loads software (computer programs) from the memory1303 and executes the loaded software (computer programs), therebyperforming processing of the server 140 described with reference to thesequence diagram and the flowchart in the above-described embodiments.The processor 1302 may be, for example, a microprocessor, an MPU, or aCPU. The processor 1302 may include a plurality of processors.

The memory 1303 is composed of a combination of a volatile memory and anon-volatile memory. The memory 1303 may include a storage that islocated away from the processor 1302. In this case, the processor 1302may access the memory 1303 via an I/O interface (not shown).

In the example shown in FIG. 13, the memory 1303 is used to storesoftware modules. The processor 1302 loads these software modules fromthe memory 1303 and executes the loaded software modules, therebyperforming processing of the server 140 described in the aboveembodiments.

As described above with reference to FIGS. 11-13, each of the processorsincluded in the UEs 100-102, the RSUs 120 and 320, the eNB 130, and theserver 140 according to the above embodiments executes one or moreprograms including instructions to cause a computer to perform analgorithm described with reference to the drawings. The program(s) canbe stored and provided to a computer using any type of non-transitorycomputer readable media. Non-transitory computer readable media includeany type of tangible storage media. Examples of non-transitory computerreadable media include magnetic storage media (such as flexible disks,magnetic tapes, hard disk drives, etc.), optical magnetic storage media(e.g., magneto-optical disks), Compact Disc Read Only Memory (CD-ROM),CD-R, CD-R/W, and semiconductor memories (such as mask ROM, ProgrammableROM (PROM), Erasable PROM (EPROM), flash ROM, Random Access Memory(RAM), etc.). The program(s) may be provided to a computer using anytype of transitory computer readable media. Examples of transitorycomputer readable media include electric signals, optical signals, andelectromagnetic waves. Transitory computer readable media can providethe program to a computer via a wired communication line (e.g., electricwires, and optical fibers) or a wireless communication line.

OTHER EMBODIMENTS

In the configuration shown in FIG. 1 or 2, the RSUs 120 and 121 each maybe configured to periodically transmit a keepalive message or aheartbeat message to the eNB 130 or the server 140. Upon failing toreceive a keep-alive or heartbeat message from an RSU, the eNB 130 orthe server 140 may detect that a fault has occurred in this RSU.Further, when determining at least one of: a sending node(s); an area; adistribution path; and a communication scheme, to distribute the V2Xcontrol message 170 as described in the above embodiments, the eNB 130or the server 140 may exclude this RSU, in which a failure has beendetected, from the candidates for the sending node(s), the area, or thedistribution path.

The above embodiments provides some examples to enable the server 140 orthe eNB 130 to easily and efficiently determine at least one of: (a) oneor more sending nodes to transmit the V2X control message 170; (b) ageographical area in which the V2X control message 170 is to betransmitted; (c) a distribution path of the V2X control message to oneor more sending nodes; and (d) a communication scheme to be used fortransmission of the V2X control message 170. The determination in (a) to(d) may be performed, for example, as shown below.

(a) Determination of One or More Sending Nodes to Transmit the V2XControl Message 170:

In one example, the server 140 or the eNB 130 may manage a list(s) ofadjacent sending nodes (e.g., a list(s) of adjacent RSUs) and select asending node(s) in the list of adjacent sending nodes that includes thereporting node (e.g., reporting RSU) to transmit the V2X control message170. In another example, the server 140 or the eNB 130 may select one ormore sending nodes that have the same group ID as the reporting node totransmit the V2X control message 170.

(b) Determination of a Geographical Area in which the V2X ControlMessage 170 is to be Transmitted:

In one example, the server 140 or the eNB 130 may select one or moresending nodes that belong in the same Tracking Area (TA) or Routing Area(RA) as the reporting node to transmit the V2X control message 170. Inother words, the server 140 or the eNB 130 may designate a TA or RA asthe geographical area in which the V2X control message 170 is to betransmitted. In another example, the server 140 or the eNB 130 mayselect a sending node(s) located in a certain area including the GNSSlocation coordinates of the reporting node, to transmit the V2X controlmessage 170. In another example, the server 140 or the eNB 130 maydesignate a geographical area based on the V2X service area (V2X SA) towhich the reporting node belongs as the geographical area in which theV2X control message 170 is to be transmitted. In other words, the server140 or the eNB 130 may designate a geographical area based on GNSSlocation coordinates as the geographical area in which the V2X controlmessage 170 is to be transmitted. Further, in another example, theserver 140 or the eNB 130 may select one or more sending nodes installedon the same road as the reporting node, to transmit the V2X controlmessage 170. In other words, the server 140 or the eNB 130 may designatea road as the geographical area in which the V2X control message 170 isto be transmitted.

(c) Determination of a Distribution Path of the V2X Control Message toOne or More Sending Nodes:

In one example, the server 140 or the eNB 130 may select, based on thelocation-related information about the reporting RSU, a communicationpath that can be used for message distribution to the surroundings ofthe reporting RSU. In another example, the server 140 or the eNB 130 mayselect, based on the location-related information about the reportingRSU, a communication path that can be used for message distribution toone or more other RSUs managed by the same cellular communicationnetwork as the reporting RSU.

(d) Determination of a Communication Scheme to be Used for Transmissionof the V2X Control Message 170:

In one example, the server 140 or the eNB 130 may select, based on thelocation-related information about the reporting RSU, a communicationscheme that can be used for message distribution to the surroundings ofthe reporting RSU. In another example, the server 140 or the eNB 130 mayselect, based on the location-related information about the reportingRSU, a communication scheme provided by the cellular communicationnetwork that manages the reporting RSU (i.e., a communication schemethat can be used for message distribution to one or more other RSUsmanaged by the same cellular communication network as the reportingRSU).

Further, a group ID or type of an RSU may indicate characteristics ofthe road on which this RSU is installed. When, for example, there areRSUs installed respectively for an inbound lane and an outbound lane(i.e., when a cell formed by each RSU is mapped only into an outboundlane or an inbound lane), an RSU group ID or RSU type may indicate alane (i.e., outbound or inbound). For example, an RSU having the groupID or type indicating “inbound lane” detects an event occurred on theinbound lane (e.g., occurrence of an accident or a traffic jam) and thensends to a server a report indicating that the event has occurred,enabling the server to select an RSU(s) having the same group ID or typeas the reporting RSU to transmit the V2X control message.

Alternatively, the group ID or type of an RSU may indicate a type ofroad. For example, there are a general road (or expressway) on anelevated structure and an expressway (or general road) under thiselevated structure. Further, for example, there are a general road (orexpressway) on the ground and an underground expressway (or generalroad) underneath of the general road (or expressway). In these cases,the group ID or type of an RSU may set to “on an elevated structure” or“under an elevated structure”, to “on the ground” or “underground”, orto “an expressway” or “a general road”. For example, an RSU having theRSU group ID or type indicating “on an elevated structure” or “anexpressway” sends to a server a report indicating an event that hasoccurred in the expressway on the elevated structure (e.g., occurrenceof an accident or a traffic jam), enabling the server to select one ormore RSUs having the same RSU group ID or type as the reporting RSU totransmit the V2X control message.

The descriptions of the above-described embodiments mainly focus onLTE/LTE-Advanced and extensions thereof. However, the above-describedembodiments may be applied to other radio communication networks orsystems.

Further, the embodiments described above are merely examples ofapplications of the technical ideas obtained by the present inventors.Needless to say, these technical ideas are not limited to theabove-described embodiments and various modifications can be madethereto.

For example, the whole or part of the embodiments disclosed above can bedescribed as, but not limited to, the following supplementary notes.

(Supplementary Note A1)

A Road Side Unit (RSU) apparatus supporting a Vehicle-to-Everything(V2X) service, the RSU apparatus comprising:

a wireless transceiver configured to communicate with a radio terminalinstalled in a vehicle; and

at least one processor configured to transmit V2X report information toa control node and to transmit location-related information about theRSU apparatus to the control node.

(Supplementary Note A2)

The RSU apparatus according to Supplementary Note A1, wherein thelocation-related information is used by the control node to determine atleast one of:

(a) one or more sending nodes to transmit a V2X control messagegenerated based on the V2X report information in such a way that aplurality of vehicles are able to receive the V2X control message;(b) a geographical area in which the V2X control message is to betransmitted;(c) a logical area in which the V2X control message is to betransmitted;(d) a distribution path of the V2X control message to the one or moresending nodes; and(e) a communication scheme to be used for transmission of the V2Xcontrol message.

(Supplementary Note A3)

The RSU apparatus according to Supplementary Note A2, wherein thecommunication scheme is selected from among a plurality of communicationschemes including at least two of (a) a Multimedia Broadcast/MulticastService (MBMS), (b) a Cell Broadcast Service (CBS), and (c) agroupcast/broadcast in Device-to-Device communication.

(Supplementary Note A4)

The RSU apparatus according to Supplementary Note A2 or A3, wherein theone or more sending nodes comprises: (a) one or more base stations usedin a cellular communication network; (b) one or more RSUs, each of whichoperates as a base station used in a cellular communication network; (c)one or more RSUs, each of which operates as a radio terminal used in acellular communication network; or (d) any combination thereof.

(Supplementary Note A5)

The RSU apparatus according to any one of Supplementary Notes A1 to A4,wherein the location-related information comprises at least one of: apre-configured RSU identifier; a pre-configured management areaidentifier; and location information indicating location coordinates ora location address of the RSU apparatus.

(Supplementary Note A6)

The RSU apparatus according to any one of Supplementary Notes A1 to A4,wherein the RSU apparatus is configured to operate as a radio terminalor a base station used in a cellular communication network.

(Supplementary Note A7)

The RSU apparatus according to any one of Supplementary Notes A1 to A6,wherein the V2X report information contains a message that the RSUapparatus has received via V2I communication from a radio terminalinstalled in a vehicle.

(Supplementary Note B1)

A base station apparatus used in a cellular communication network, thebase station apparatus comprising:

a wireless transceiver configured to communicate with a plurality ofradio terminals including one or more Road Side Units (RSUs) supportinga Vehicle-to-Everything (V2X) service; and

at least one processor configured to transmit V2X report informationreceived from a first RSU included in the one or more RSUs to a controlnode and to transmit location-related information about the first RSU tothe control node.

(Supplementary Note B2)

The base station apparatus according to Supplementary Note B1, whereinthe location-related information is used by the control node todetermine at least one of:

(a) one or more sending nodes to transmit a V2X control messagegenerated based on the V2X report information in such a way that aplurality of vehicles are able to receive the V2X control message;(b) a geographical area in which the V2X control message is to betransmitted;(c) a logical area in which the V2X control message is to betransmitted;(d) a distribution path of the V2X control message to the one or moresending nodes; and(e) a communication scheme to be used for transmission of the V2Xcontrol message.

(Supplementary Note B3)

The base station apparatus according to Supplementary Note B2, whereinthe communication scheme is selected from among a plurality ofcommunication schemes including at least two of (a) a MultimediaBroadcast/Multicast Service (MBMS), (b) a Cell Broadcast Service (CBS),and (c) a groupcast/broadcast in Device-to-Device communication.

(Supplementary Note B4)

The base station apparatus according to Supplementary Note B2 or B3,wherein the one or more sending nodes comprises: (a) one or more basestations used in a cellular communication network; (b) one or more RSUs,each of which operates as a base station used in a cellularcommunication network; (c) one or more RSUs, each of which operates as aradio terminal used in a cellular communication network; or (d) anycombination thereof.

(Supplementary Note B5)

The base station apparatus according to any one of Supplementary NotesB1 to B4, wherein the location-related information comprises at leastone of: a pre-configured RSU identifier; a pre-configured managementarea identifier; and location information indicating locationcoordinates or a location address of the first RSU.

(Supplementary Note B6)

The base station apparatus according to any one of Supplementary NotesB1 to B5, wherein the V2X report information contains a message that thefirst RSU has received via V2I communication from a radio terminalinstalled in a vehicle.

(Supplementary Note C1)

A control node comprising:

a memory; and

at least one processor coupled to the memory and configured todetermine, based on location-related information about a first Road SideUnit (RSU) supporting a Vehicle-to-Everything (V2X) service, at leastone of:

(a) one or more sending nodes to transmit a V2X control messagegenerated based on V2X report information transmitted by the first RSUin such a way that a plurality of vehicles are able to receive the V2Xcontrol message;(b) a geographical area in which the V2X control message is to betransmitted;(c) a logical area in which the V2X control message is to betransmitted;(d) a distribution path of the V2X control message to the one or moresending nodes; and(e) a communication scheme to be used for transmission of the V2Xcontrol message.

(Supplementary Note C2)

The control node according to Supplementary Note C1, wherein thelocation-related information comprises at least one of: a pre-configuredRSU identifier; a pre-configured management area identifier; andlocation information indicating location coordinates or a locationaddress of the first RSU.

(Supplementary Note C3)

The control node according to Supplementary Note C1 or C2, wherein thecommunication scheme is selected from among a plurality of communicationschemes including at least two of (a) a Multimedia Broadcast/MulticastService (MBMS), (b) a Cell Broadcast Service (CBS), and (c) agroupcast/broadcast in Device-to-Device communication.

(Supplementary Note C4)

The control node according to any one of Supplementary Notes C1 to C3,wherein the one or more sending nodes comprises: (a) one or more basestations used in a cellular communication network; (b) one or more RSUs,each of which operates as a base station used in a cellularcommunication network; (c) one or more RSUs, each of which operates as aradio terminal used in a cellular communication network; or (d) anycombination thereof.

(Supplementary Note C5)

The control node according to Supplementary Note C4, wherein

the at least one processor is configured to determine, based on thelocation-related information, the one or more RSUs as the one or moresending nodes, and

the at least one processor is further configured to determine at leastone of the distribution path and the communication scheme based on atype of the one or more RSUs.

(Supplementary Note C6)

The control node according to any one of Supplementary Note C1 to C5,wherein the at least one processor is further configured to generate theV2X control message in response to reception of the V2X reportinformation.

(Supplementary Note C7)

The control node according to any one of Supplementary Note C1 to C5,wherein the at least one processor is further configured to receive froman external node the V2X control message generated based on the V2Xreport information, and to determine, based on a type or a content ofthe V2X control message, at least one of: the one or more sending nodes;the geographical area; the logical area; the distribution path; and thecommunication scheme.

(Supplementary Note C8)

The control node according to any one of Supplementary Notes C1 to C5,wherein

the at least one processor is further configured to receive from anexternal node the V2X control message generated based on the V2X reportinformation, and to determine, in accordance with a bearer used totransmit the V2X control message from the external node to the controlnode, at least one of: the one or more sending nodes; the geographicalarea; the logical area; the distribution path; and the communicationscheme, and

the bearer is associated in advance with a type or a content of the V2Xcontrol message.

This application is based upon and claims the benefit of priority fromJapanese Patent Application No. 2015-185291, filed on Sep. 18, 2015, thedisclosure of which is incorporated herein in its entirety by reference.

REFERENCE SIGNS LIST

-   100-102 UE-   120, 121 RSU-   121 RSU-   130 eNB-   140 SERVER-   150 NOTIFICATION-   160 V2X REPORT INFORMATION-   170 V2X CONTROL MESSAGE-   320, 321 RSU-   1001 RF TRANSCEIVER-   1004 PROCESSOR-   1101 RF TRANSCEIVER-   1103 BASEBAND PROCESSOR-   1104 APPLICATION PROCESSOR-   1202 PROCESSOR-   1203 MEMORY

1. A Road Side Unit (RSU) apparatus supporting a Vehicle-to-Everything(V2X) service, the RSU apparatus comprising: a wireless transceiverconfigured to communicate with a radio terminal installed in a vehicle;and at least one processor configured to transmit V2X report informationto a control node and to transmit location-related information about theRSU apparatus to the control node, wherein the location-relatedinformation is used by the control node to determine a logical area inwhich a V2X control message generated in response to the V2X reportinformation is to be transmitted, the V2X report information includesinformation related to an accident, and the V2X control message includesa warning about the accident.
 2. The RSU apparatus according to claim 1,wherein the location-related information comprises at least one of: apre-configured RSU identifier; a pre-configured management areaidentifier; and location information indicating location coordinates ora location address of the RSU apparatus.
 3. A base station apparatusused in a cellular communication network, the base station apparatuscomprising: a wireless transceiver configured to communicate with aplurality of radio terminals including one or more Road Side Units(RSUs) supporting a Vehicle-to-Everything (V2X) service; and at leastone processor configured to transmit V2X report information receivedfrom a first RSU included in the one or more RSUs to a control node andto transmit location-related information about the first RSU to thecontrol node, wherein the location-related information is used by thecontrol node to determine a logical area in which a V2X control messagegenerated in response to the V2X report information is to betransmitted, the V2X report information includes information related toan accident, and the V2X control message includes a warning about theaccident.
 4. The base station apparatus according to claim 3, whereinthe location-related information comprises at least one of: apre-configured RSU identifier; a pre-configured management areaidentifier; and location information indicating location coordinates ora location address of the RSU apparatus.
 5. A method performed by a RoadSide Unit (RSU) apparatus supporting a Vehicle-to-Everything (V2X)service, the method comprising: transmitting V2X report information to acontrol node; and transmitting location-related information about theRSU apparatus to the control node, wherein the location-relatedinformation is used by the control node to determine a logical area inwhich a V2X control message generated in response to the V2X reportinformation is to be transmitted, the V2X report information includesinformation related to an accident, and the V2X control message includesa warning about the accident.
 6. The method according to claim 5,wherein the location-related information comprises at least one of: apre-configured RSU identifier; a pre-configured management areaidentifier; and location information indicating location coordinates ora location address of the RSU apparatus.
 7. A method performed by a basestation apparatus used in a cellular communication network, the methodcomprising: communicating with a plurality of radio terminals includingone or more Road Side Units (RSUs) supporting a Vehicle-to-Everything(V2X) service; transmitting V2X report information received from a firstRSU included in the one or more RSUs to a control node; and transmittinglocation-related information about the first RSU to the control node,wherein the location-related information is used by the control node todetermine a logical area in which a V2X control message generated inresponse to the V2X report information is to be transmitted, the V2Xreport information includes information related to an accident, and theV2X control message includes a warning about the accident.
 8. The methodaccording to claim 7, wherein the location-related information comprisesat least one of: a pre-configured RSU identifier; a pre-configuredmanagement area identifier; and location information indicating locationcoordinates or a location address of the RSU apparatus.